Frank l



F. L. SESSIONS.

APPARATUS FOR ELECTRIC WELDING.

APPLICATION FILED MAY 5. 1919.

14,927. 2 SHEETS-SHEET 1.

- lnvcutor flan/PL Jmz'ons Reissued July 27, 1920.

Gttorncg .F. L. SESSIONS-J APPARATUS run ELECTRIC WELDING.

APPLICATION FILED MAY 5, 191.9. n Reissued July 27, 1920. 14,927.

2 SHEETS-SHEET 2.

31l vcntor flank L. Sam-20225 Gttorncg UNITED isrAre's PATENT-OFFICE.

FRANK L. SESSIONS, or naxnwoon, .omo, ASSIGNOR, BY MESNE assrenmmrrsfiroTHE STANDARD PARTS co rrnzw, or CLEVELAND, care, A CORPORATION or 01110,

airamrus FOR ELECTRIC wnnnmo.

26, 1918, Serial No. 231,025.

To all whom it may concern:

Be it known that I, FRANK L. SESSION S, a citizen of the United States,and a rest dent of Lakewood, county of Guyahoga, and State of Ohio, haveinvented a new and useful Improvement in Apparatus for Electric Welding,of which the following is a specification, the principle of thelnvention being herein explained and the best mode in which I havecontemplated applying that principle, soas to dist1ngu1sh it from otherinventions.

The present invention relates more particularly to the welding togetherof the uxtaposed edges of two sheets of metal, or

the abutting edges of one sheet bent into ously, and, if desired,automatically, at the proper rate of speed to insure the expeditious andyet thorough welding of the 101m; between such juxtaposed edges. To'theaccomplishment of theforegoing and related ends the invention, then,consists of the steps and means heneinafter fully described andparticularly pointed out in the claims.

The annexed drawings and the following description set forth in detailcertain steps and mechanism embodying the invention, such disclosedmeans constituting, however,

but several of the various ways in which the principle of the inventionmay be used.

In said annexed draw1ngs: Figure l is a side elevational new, more orless diagrammatic in character, i-llustrating an apparatus adapted toweld together the edges of. a metal 'tube in accordance with my improvedmethod;

Fig. 2 is a similar View of a modified form of the apparatus;

Fig. 3 is an elevation of the same as viewed from the right in Fig. 2;

Fig. 4: is a plan View, with parts shown in section, illustrating yetanother modification of the apparatus;

Fig. 5 is a side elevational view of such last-named modification; and

Fig. 6 is a cross-sect1on showing the Specification of Reissued LettersPatent. Rei d Ji l 27 19 0 Original No; 1,287,774, dated December 17,1918; Serial No. 779,674, filed July l8, 1913. Renewed April Applicationforreissue filed-May 5, 1919-.- Serial No. 295,010.

welding operation on a larger scale and with a further modification, oraddition,-in apparatus.

Any suitable feeding means for forcing or pulling the tube A through thewelding apparatus proper may be emp-lo ed, but one or more pairs of feedrolls 1,'il ustrated in Figs. 1 and 4 of the foregoing figures, areadapted for carrying out this part of the operation. By means of saidfeed rolls, the tube is drawn through between two pressure rolls 2 whichare disposed so as to tend to force the butt edges of the tube more orless closely together. Disposed directly above these pressure rolls 2 isa suitable feeding device shown as consisting of two rolls S'betweenwhich passes a continuous metallic electrode B of indefinite length,such electrode under operating conditions, being initially forceddownwardly until it .is in contact with the abutting edges of thetubing" to be welded, then slightly withdrawn so as to form an arc, andbeing then maintained in such arcing distance.

In the first and simplest form of apparatus illustrated (Fig. 1), a handwheel 4 is arranged to rotate a Worm 5 that meshes with a worm wheel 6on one of the rolls 3, and such wire electrode may be fed at any desiredrate, to correspond with the rate of feed of the tube by properlyrotating saidhand wheel 4. The wire is conveniently coiled on a reel 7or the like, from which it is drawn by the aforesaid feeding device anda guide 8 of refractory material may be utilized, if desired, to directthe wire to the proper point on the tubing.

Current may be supplied from any suitable source, as a generator 9, andis conveniently conducted to the tubing through the pressure rolls 2 andto the wire electrode through the feed rolls 3. Such current accordinglywill pass from the electrode to the respective abutting edges of thetube, or vice versa, as the case may be,-the are formed between the twoserving -to heat such edges and the end of the electrode simultaneously.The current will be regulated to develop sufficient heat to graduallymelt the electrode and as it thus melts the tubing willbe advanced bymeans of the feed rolls-so that such melted electrode will be disposedin the joint between the edges. The latter being simultaneously broughtto same onto a corresponding temperature, a continuously welded joint isformed which I have found can be made quite satisfactory for allpuroses, and in fact superior tothe ordinary utt-welded join Themetallic electrode being of an indefinite length, and means being provded as just described for continuously feeding the between which thetube A to be welded is passed. To this end, instead of the spindle withhand wheel 4 having a worm gear connection with the roll, I employ avertically disposed spindle 10 connected with one of said feed rolls bygears 11 and provided at its upper end with a worm 12 that meshes with aworm-gear 13 on one such roll 3, the ratio of the gears 11, 12 and 13being proportioned to feed the electrode at just the ro er rate tocorrespond with the rate of ee of the work. It will be understood thatthe pressure rolls in this construction, as well as in the precedingone, are power driven.

The apparatus illustrated in Figs. 4 and 5 is further elaborated by theinclusion of means for automatically regulating the rate of feed of thewire electrode B to correspond with the progress of the weldingoperation. In addition to the feed rolls 1 and the pressure rolls 2which are disposed substantially as before,there is provided in thislast form of apparatus a solenoid 14 that is adapted to be actuated bythe current flowing through the work and the wire electrode. Thissolenoid operates a bell-crank 15 which is, in turn, connected to throwin or out a double clutch 16, through which rotative movement istransmitted from a drive shaft 17, to a second shaft 18 that carries oneof the feed rolls 3 for feeding the wire electrode. When such clutch isthrown to the right, the feed is direct and at a predetermined speed,while if the clutch 'is thrown to the left the feed is reversed so as totemporarily withdraw the electrode. In the intermediate position of theclutch, which is the one show-n in Fig. 4, the feeding of the electrodewill be simply interrupted and such electrode temporarily heldstationary. I I

A spring 19, however, is so connected with the bell-crank 15 or otherpart of the automatic feeding device as to normally tend to throw theclutch into direct, or forward, feed. Accordingly, upon starting up theapthe work, there need be no interparatus, assuming the current to beon, (the circuit connections being controlled by a switch 20), if theshaft 17 is started rotating, the electrode will be fed forwardly untilits end actually contacts with thejuxtaposed edges of the tube A,thereby completing the circuit and causing such a flow of current aswill actuate the solenoid to throw the clutch into reverse. Thereversing of the feed will withdraw the electrode a trifle, justsufficient, in fact, to remove the end of the electrode the properdistance from said edges to establish an arc. With such are establishedthe flow of current from the circuit, although reduced, will stillpermit the clutch to drive the feed rolls forwardly andthus continuouslyfeed the electrode at a rate capable of maintaining its end within sucharcing distance, despite the gradual fusing of the end. The work beingprogressively advanced past the end of the. electrode, the juxtaposededges are brought substantially to a point of fusion, as the meltedmaterial from the electrode is deposited between the same.

Should the electrode be fed too rapidly, so as to again bring the sameinto actual contact with the work, the solenoid will be actuated by theincreased fiow of current to interrupt the feeding operation, oroven toreverse the same. As soon, however, as the distance of the electrodefrom the work is restored to normal, the clutch is thrown into theforward feeding position and the operation proceeded with. The operationof the solenoid may be very sensitive so that a very exact control ofthe feeding operation is secured, the wire electrode being advanced atjust the proper speed to give the desired welding effect. The tension ofspring 19 may be adjusted by means of a nut 22.

In rolling up the sheet or strip of metal to preliminarily form the tubefor use in the ordinary butt-welding operation, it is usual to stretchthe outer surface of the sheet so that the juxtaposed edges may lie insubstantially the same radial plane with respect to the axis of thetube. For use in the present'improved process, however, it is notnecessary to do this, and in fact it is preferable that the edges a beleft in their normal state so that they flare a trifle and thus form asort of trough, as illustrated in somewhat exaggerated fashion in Fig.6. In other words, the extreme inner portion of the meeting faces willcome into closer contact than the outer portion of such faces,

and the fused metal 3 that is deposited from of porcelain or otherrefractory material This latter so as to form a complete closure forttie space between such juxtaposed edges.

The arrangement 'ust referred to is also illustrated in said i 6, itbeing considered unnecessary to il ustrate the means'of supporting themandrel as these may be readily improvised, and will vary depend in uponwhether the tube is preliminarily ro led up in sections of considerablelen th, or is continuously rolled up, as the wel mg operationprogresses, from a long strip of metal as it comes from the skelpingrolls.

Suitable insulation will of course be provided in each of the severalforms of apparatus described above, so as to prevent the current fromstraying. The particular disposition of such insulation, however, isobvlously a matter of indifference and no attempt has been made to showthe same in detail in the drawings.

While the several foregoing described forms of apparatus for use in myimproved method are illustrated as adapted for welding the edges oftubing together, it will be understood that the apparatus maybe equallywell utilized for welding together the juxtaposed edges of separatesheets'or other articles. Accordingly for the purpose of thisspecification and the following claims, the respective edge portions ofthe tube may be regarded simply as two metallic articles, although theyform part of the same tube. My improved process, however, does find ahighly advantageous field of use in the manu acture of tubing, since bymeans of it tubing of indefinite length can be made from a strip orskelp, being fed through, the welding apparatus, while a metallicelectrode, of like-indefinite length is progressively brought intoproximity with the contacting or substantially contacting edges of thetube. The current, it will be observed, by reason of the circuitconnections employed, is passed through such ed es of the tube and theelectrode.

ather modes of applying the principle of my invention may be employedinstead of the one explained, change being made as regards the steps ormechanism herein disclosed, provided the means stated by any of thefollowing claims or the equivalent of such stated means be employed. I

I therefore particularly point out and distinctl claim as my invention:-

1. Iii apparatus for electrically welding tubing, the combination ofpressure rolls adapted to maintain the edges of a preliminarily formedtube in substantial contact; means adapted to feed a metallic electrodetransversely of such tube toward such edges;

means adapted tofeed such tube longitudinally so as to move such edgesprogressively past'the end of said electrode; circuit connections forpassing a fusing electric current through said electrode to both suchedges; a: suitable driver; a clutch for opera-- tively connecting saidelectrode feeding means with said driver; and electro-magnetic meansconnected in such circuit and adapted to operate said clutch. 2. Inapparatus for electrically welding tubing, the combination of pressurerolls adapted to maintain the edges of a preliminarily formed tube insubstantial contact;

means adapted to feed a metallic electrode transversely of such tubetoward such edges;

means adapted to feed such tube longitudinally so as to move such edgesprogressively past the end of said electrode; circuit connections forpassing a fusing electric current through said electrode to both suchedges; a suitable driver; a clutch adapted qptionally to connect saidelectrode feeding fn'eansdirectly or reversely with said driver; andelectro-magnetic means connected in such circuit and adapted to operatesaid clutch.

3. In apparatus for continuous electric welding, the combination ofmeans for feeding the work; means for maintaining the edges to bewelded'together in substantial contact; rotar means adapted to grip afusible metallic electrode and feed same transversely of the line offeeding movement of the work; circuit connections for passing a fusingcurrent through said electrode to such edges; and rotary meanscontrolled by the fusing current for automatically regulating therelative feeding movements of said electrode and thework.

4. In apparatus for electrically welding tubing, the combination ofmeans for maintaining the edges of a preliminarily formed tube insubstantial contact; rotary means adapted to grip a metallic electrodeand 105 feed same transversely of such tube; means adapted to feed thetube longitudinally so as to move such edges progressively past the endof said electrode; circuit connections for passing a fusin currentthrough such 11o electrode to such e' ges; and rotary meansautomatically controlled by the fusing current in said circuit, foractuating said rotary feeding means.

5. In apparatus for continuous electric Welding, the combination ofmeans for feeding the work; means for maintaining the edges to-be weldedtogether in substantial contact; means adapted to grip a fusiblemetallic electrode and feed same trans- 120 versely of the line offeeding movement of the work; circuit connections for passing a fusingcurrent through said electrode to. such edges; and'rotary means governedby the fusing current to automatically control 12;, said electrodefeeding means so that the rate of feeding of said electrode .will be inaccordance with the variations in the fusing current.

welding, a fusible metallic electrode, means to grip said electrode andfeed the same toward the work to be welded, circuit connections forpassing a fusing electric current through said electrode to the Work,and devices governed by the fusing current to start the arc and toautomatically control said electrode feeding means so that the rate offeeding of said electrode will be in accordancte with the variations inthe fusing cur- 10 ren Signed by me this 3d day of May, 1919.

FRANK L. SESSIONS.

